\(K = \frac{{[{H^ + }]\,\,[O{H^ - }]}}{{({H_2}O)}} = C{\alpha ^2}\)
\( = 1.9 \times {10^{ - 9}} \times 1.9 \times {10^{ - 9}} \times \frac{{1000}}{{18}}\)\( = 2.0 \times {10^{ - 16}}\).
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